Attempting to replace a dead link with your own is easily and routinely identified as spam by the Wikipedia community, which expects dead links to be replaced to equivalent links at Persistent attempts will quickly get your account blocked, and your webiste can be blacklisted (the Wikipedia blacklist is public, and there is evidence that Google uses it to determine rankings), which will have negative SEO consequences.
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Early versions of search algorithms relied on webmaster-provided information such as the keyword meta tag or index files in engines like ALIWEB. Meta tags provide a guide to each page's content. Using metadata to index pages was found to be less than reliable, however, because the webmaster's choice of keywords in the meta tag could potentially be an inaccurate representation of the site's actual content. Inaccurate, incomplete, and inconsistent data in meta tags could and did cause pages to rank for irrelevant searches.[10][dubious – discuss] Web content providers also manipulated some attributes within the HTML source of a page in an attempt to rank well in search engines.[11] By 1997, search engine designers recognized that webmasters were making efforts to rank well in their search engine, and that some webmasters were even manipulating their rankings in search results by stuffing pages with excessive or irrelevant keywords. Early search engines, such as Altavista and Infoseek, adjusted their algorithms to prevent webmasters from manipulating rankings.[12]
Expert roundups have been abused in the Internet Marketing industry, but they are effective for several reasons. First, you don’t have to create any content. The “experts” create all the content. Second, it is ego bait. Meaning, anyone who participated in the roundup will likely share it with their audience. Last, it is a great way to build relationships with influencers.
To prevent users from linking to one version of a URL and others linking to a different version (this could split the reputation of that content between the URLs), focus on using and referring to one URL in the structure and internal linking of your pages. If you do find that people are accessing the same content through multiple URLs, setting up a 301 redirect32 from non-preferred URLs to the dominant URL is a good solution for this. You may also use canonical URL or use the rel="canonical"33 link element if you cannot redirect.
Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve deception. One black hat technique uses hidden text, either as text colored similar to the background, in an invisible div, or positioned off screen. Another method gives a different page depending on whether the page is being requested by a human visitor or a search engine, a technique known as cloaking. Another category sometimes used is grey hat SEO. This is in between black hat and white hat approaches, where the methods employed avoid the site being penalized but do not act in producing the best content for users. Grey hat SEO is entirely focused on improving search engine rankings.
While most of the links to your site will be added gradually, as people discover your content through search or other ways and link to it, Google understands that you'd like to let others know about the hard work you've put into your content. Effectively promoting your new content will lead to faster discovery by those who are interested in the same subject. As with most points covered in this document, taking these recommendations to an extreme could actually harm the reputation of your site.
Dedicate some time to brainstorm all the different ways you can attract inbound links to your website. Start small –- maybe share your links with other local businesses in exchange for links to their sites. Write a few blog posts and share them on Twitter, Facebook, Google+, and LinkedIn. Consider approaching other bloggers for guest blogging opportunities through which you can link back to your website.

Provide full functionality on all devices. Mobile users expect the same functionality - such as commenting and check-out - and content on mobile as well as on all other devices that your website supports. In addition to textual content, make sure that all important images and videos are embedded and accessible on mobile devices. For search engines, provide all structured data and other metadata - such as titles, descriptions, link-elements, and other meta-tags - on all versions of the pages. 

Nice work Laura! This is going to be a great series. I'm working my way through SEOmoz's Advanced SEO Training Series (videos) Vol. 1 & 2 to build upon the advice and guidance that you and your team provided to me during my time at Yahoo!. Now many others will benefit from your knowledge, experience and passion for SEO strategy and tactics. Best wishes for great success in your new role.